Fine adjustment means for microscopes



May 29, 1956 c. .1. BOWERMAN FINE ADJUSTMENT MEANS FOR MICROSCOPES Filed Feb. 19, 1954 IN VEN TOR.

BY ma@ A T TIZNEX CLARENCE J. BOWERMAN United States Patent() Bausch & Lomb Optical Company, Rochester, N. Y., a corporation of New York Application February .19, 1954, serial No. 411,3?2 4 Claims. (Cl. 8'8-39) This invention relates to microscopes and more particularly to a tine adjustment meehanism therefor.

One of the objects of this invention is to provide an improved tine adjusting mechanism which is relatively simple in structure, `'neat in appearance, economical 'to manufacture and yet efficient -in operation.

Another object of this invention is to provide an improved ne adjusting 'mechanism which is coaxially mounted relative to .the coarse adjusting mechanism.

A further object of this invention is to provide an improved ne adjusting meehanism having an actuating knob so arranged relative to the 'microscope and to the coarse adjusting mechanism as to alford a maximum of convenience and comfort to the user.

These and other objects and advantages reside in certain novel features o'f construction, arrangement and combination of parts as will hereinafter be more fully described and pointed out -i-n 'the appended claims.

Referring to the drawings:

Fig. l is a fragmentary view of `a microscope stand showing a preferred form of the invention embodied therein.

Fig. 2 is a fragmentary vertical section of the coarse and ne adjustment mechanism.

Fig. 3 is a section taken 'on line 3-3 of Fig. 2.

Fig. 4 is a section taken on line 4-4 of Fig. v2.

One embodiment of "my invention is illustrated in the drawing wherein designates a base having an upstanding support 11 which has a vertically movable substage 'condenser lens member 12 aligned with a specimen stage member 13. Although the preferred form of my invention is shown 'with a coarse adjusting mechanism '15 and a nue adjusting mechanism 16 for moving the substage condenser lens lmember 132, it is to be understood that said adjusting mechanisms and 16 could be used for adjustinga movable specimen stage or a movable lens carrying body' tube member without departing from the spirit of nly invention. The substage condenser lens member 12, slidably mounted on slideways 18 and 19 for focusing .pur-poses, vhas attached lon one side thereof a rack 29 adapted 'to move vertically with said condenser lens member 12.

Mounted on the support .11 'and extending through an opening 22 therein is an elongated tubular housing 23 having intermediate its end portions, 25 and 26, a flange member 27 through which screws 28 pass into threaded engagement with the support 11 for holding the adjusting mechanisms 15 and 16 in operative position relative to the rack 20. Slidably mounted coaxial with and having aportion thereof extending into the housing 23 is a cylindrical sliding 4member or sleeve 30 which has a longitudinal keyway 31 in an outer wall .in engaging relation with a key 32 mounted on the inside wall of the housing 23, 'said key 32 and keyway 31 permitting said sleeve 30 to slide axially relative to the Ahousing 23. Coaxially mounted within said sleeve 30 to lmove axially therewith and rotate relative thereto is a Ishaft 34 which has a Y, 2,747,464 Patented May 29, 1956 coarse adjusting knob 35 mounted on one end portion and has a helical pinion 36 mounted thereon adjacent the other end portion, said pinion 36 being in operative engagement with said rack 20 so that rotation of the knob 35 Will rotate the pinion 36 to effect coarse adjustment of the condenser lens member 12.

The shaft 34V has two bearing surfaces 37 which rotate freely on the bearing surfaces on the sleeve 30 vfor supporting said shaft relative to said housing. Nylon washers 3'8 and 39 are mounted on the shaft 34 and are positioned, respectively, between one end of the sleeve 30 and pinion 36 and between knob 35 and a spring washer 4l), said spring washer 40 bearing against the other end of the sleeve 30. The knob 35 may be shifted axially of the shaft 34 to any selected position by 'turning an adjusting 'screw 42 in the end of the shaft 34. A lock screw 43 is threaded in the knob 35 into engaging relation with a sl-ot 44 in 'the' side ofthe shaft 34 for locking the knob 35 on 'the shaft 34 in 'the selected position.

Advancing said screw 42 compresses the spring Washer 40 against the sleeve 30 for increasing the amount of drag between the knob 35 and the sleeve 30 to provide resistance against the rotation of Vthe pinion 36. This drag between the sleeve 30, knob 35 and pinion 36 prevents 'the pinion 36 from rotating relative to the sleeve during certain operations of the device for a purpose to be explained vh'ereinbelow. Also, 'this aforementioned resistance or drag prevents the weight of the condenser lens member 12 from turning the pinion and 'upsetting the adjusted position of said lens member.

The fine adjustment of the condenser lens member 12 is accomplished by axially shifting said pinion 36, shaft 34, 'sleeve 36 and knob 35 relative to the housing 23 to thereby cause the teeth Ion the pinion 36 to move across the teeth on the rack 20 and by a camming action to raise or lower the condenser lens member 12 an amount less than 'the pitch of said teeth on the pinion 36. The inside portion of the housing 23 in the vicinity of the pinion 36 is large enough to permit the pinion 36 'to be freely shifted axially an amount equal at least to twice the length of said pinion 36. An actuating means or tubular knob 46, having an undercut portion 47 for telescopically fitting over the knob 35, is coaxially mounted relative to the sleeve 30 and shaft 34 and is in threaded engagement with the threads 48 on the outside of the projecting end portion 26 of the housing 23. The inner end portion of the tubular knob 46 has a semi-circular stop 49, seated by screw 5l) in an undercut portion 51, which prevents the 'tubular knob 46 from being moved axially too far in either direction.

The inner surface of 'the tubular knob 46 has a pair of axially spaced inwardly 'projecting radial shoulders 53, 54 which 'extend into operative engagement, respectively, with the vopposite sides of a radial projection 55 integrally formed on the outer surface of said sleeve 30. The shoulder 53 is formed integrally with the tubular knob 46 while the shoulder 54 is threaded into the end of said tubular knob 46. Shoulder 54 forces a nylon washer 56 against the side of the radial lprojection 55 to provide a freely sliding surface between the rotating shoulders 53, 54 and the non-rotating axially slidable radial projection 55 on sleeve 30. Mounted in the end portion 25 of the housing 23 by means of a threaded plug 57 'is a spiral spring member 58 which is in engagement with the adjacent end of the pinion 36 whereby said `spring 58 urges said pinion and adjusting mechanisms in the one direction to substantially eliminate slack and backlash from the mechanisms.

Rotation of the tubular knob 46 will move said tubular knob axially of the housing 23 along the threads 48 lon said housing; As the tubular knob 46 moves axially,

. 3 the pair of shoulders 53 and 54 in engagement with the radial projection 55 on said sleeve transmit the axial movement of the tubular knob to the sleeve 30, shaft 34, and pinion 36. The axial movement of the-pinion 36 relative tothe housing 23 will slidethe teeth on said pinion 'transversely across the rack 20 for raising or lowering the condenser lens member 12 an amount less than theV width of the pinion times the tangent of the pitch angle of theY teeth on said pinion 36.

in the-operationof my invention, the coarse adjusting Vknob 3S is rotated against the resistance created by the spring washer 4b to eifect coarse adjustment of the-condenser lens member 12 relative to the support. To etect flue adjustment of said condenser lens member 12,.the tubular ,knob 46 is rotated. Since the key 32Y engages inthe longitudinal keyway 31 to constrain the sleeve 39 to rectilinear movement axially of the sleeve 30, the rotation of the tubular knob 45 will Vcause the sleeve 30 to move axially thereof. The sleeve 3b is mountedron the shaft 34 and pinion 36 in such a way that movement of the sleeve 3@ axially in either direction will simultaneously move the shaft 34 and pinion 36 axially therewith. The movement of the pinion 36 transversely across the rack Z will raise or lower the condenser lens memberV 12 a relatively small amount. lt is imperative for the successful operation of the fine adjusting mechanism that the shaft does not rotate during the axial shifting of the sleeve; When the tubular knob 46 is rotated, the shaft 34 and pinion 36 will be held against rotation by the drag exerted on the pinion 35 and sleeve 30 by the spring washer 4%. The drag maintained by the spring washer 4i? is always sufficient to prevent the pinion 36 from rotating when the tubular knob 46 is rotated.

VFrom the foregoing, it will be apparent that I am able to attain the objects of my invention and provide improved means whereby fine adjustments of a microscope may be effected. My improved means is relatively simple in structure requiring no difficult machining operations to produce the parts thereof. The resulting mechanism provides a device that is neat in appearance Vand isv mounted on the microscope in such a way as to Ybe easily manipulated with one hand of the operator. The mechanism is economical to manufacture and eicient and accurate in operation.V Various modications of structure can, of course, be made without departing from the spirit of my invention as pointed out in the appended claims. I claim: Y 5

l. In a microscope the'combination of a support, a lens member slidably mounted on said support, a tubular housing extending throughV said support, a rack carried by lsaid member, a shaft mounted for rotational and axial movement within said housing, a helical pinion fixed on the shaft adjacent one end thereof and in operative engagement with the rack, a knob fastened on the other end of the shaft for rotating the' pinion to effect coarse Vadjustment lof said member, a sliding member positioned within the housing and extending parallel to the shaft,

Y one end of the sliding member being connected to one end of the pinion whereby motion of the sliding member will` be transmitted to the pinion, means on said sliding member and said housingfor limiting the sliding member to longitudinal movementV relative to the housing, a tubularV knob coaxially mounted relative to said shaft and in threaded envagement withthe outside of said tubular housing, coacting means on said tubular knob and said Y sliding, member for transmitting the .axial movement of the tubular knob to the sliding member, and'frictional dragmeans acting on the sliding member and the shaft nto provide resistance against rotation of the pinion whereby rotation of the tubular knobV will move the pinion least one of said members movable relative to the other, a tubular housing on said support, a rack carried by said movable member, a shaft'mounted for rotational and axial movement within said housing, helical gear means fastened on said shaft adjacent one end portion for operatively connecting the shaft to the rack, a knob fastened on the other end portion of the shaft for rotating said shaft to effect coarse adjustments of the movable member, and means for moving the pinion axially to effect tine adjustments of the movable member, said last-named means comprising a sleeve rotatably andV coaxially mounted relative to said shaft and having a portion thereof slidably mounted in said housing, yieldable means for holding said sleeve in abutting engagement with said pinion to provide resistanceagainst rotation of said pinion,

ment of said sleeve, said shaft being rotatable relative to and axially movable with said sleeve,v a tubular knob coaxially mounted relative to said shaft and sleeve and in threaded engagement with the outside of said tubular housing, and coacting means on said tubular knob and said sleeve for transmitting theV axial movement ofthe tubular knob to the sleeve whereby rotation of the tubular knob will move the pinion transversely relative to the rack to effect ine adjustment of the movable member.

3. In a microscope the combination of a support, a lens member slidably mounted on'said support, a tubular housing extending through said support, a sleeve having a portion slidably mounted withinsaid housing and having a longitudinal keyway in the outer wall thereof, a key mounted on the inside of the tubular housing in engagement with said keyway, a shaft coaxially mounted in said sleeveto move axially therewith and` rotate relative thereto, a helical pinion and a ,coarse adjusting knob fastened on Vopposite ends of said shaft, yieldable means for holding said sleeve in abutting engagement with said pinion to provide resistance against the rotation of said pinion, a rack carried by said lens member in operative Y engagement with said pinion, a tubular knob in threaded' for raising orV lowering the Vlens member in relativelyl large increments, and rotation `of the tubular knob will move the pinion transverselyrelative to the rack soVV that Y said lens member will be raised or lowered an amount less than the width of said pinion times the tangentr ofv the pitch angle ofrsaidV pinion toV effect Ltine adjustment thereof. n

4.- ,In a microscope the ,combination vof a support, a lens member slidably mountedron said support, a tubular housing extending through Ysaid support, a-sleevefhaviug a portion thereof slidably Vmounted withinv the housing and coaxial therewith, said sleeve having a longitudinal keyway in the outer wall thereof, a key mounted on the inside of the tubular housing in engaging relation with said keyway, a shaft rotatably mounted within said sleeve on bearing surfaces formed on the sleeve, said-shaft being coaxial with the sleeve and mounted to move axially therewith, a helical pinion fastened adjacent one end of the shaft, Va rack carriedby .said Vlens member in operative engagement with said pinion, a knob on the other end of the shaft for rotating the shaft to effect coarse adjustmember positioned within said housing in engagement transversely of the rack for effecting ne adjustment of with the other end of said pinion, a tubular knob cothe lens member.

axially mounted relative to said shaft and sleeve and in threaded engagement with the outside of said tubular References Cited in the file of this patent housing, a radial projection integrally formed on the outer 5 surface of said sleeve, and a pair of inwardly projecting UNITED STATES PATENTS spaced shoulders carried by the tube and in engagement, 528,211 Sedgwick Oct. 30, 1894 respectively, with the opposite sides of said radial projec- 2,421,126 Ott May 27, 1947 tion, whereby rotation of the tube will move the pinion 2,563,702 Benford Aug. 7, 1951 

